The removal of water from water-supply systems, particularly during winter months when sub-freezing temperatures may be encountered, is of great importance as standing water in a water supply system which is not used can freeze and rupture the pipes.
Even though great care may be taken to drain such water systems, frequently there are pockets of water remaining in fittings, elbows, and the like which cannot be easily reached and the trapped water can freeze and produce rupture of various parts.
It is known to blow compressed air through pipes in order to expel any water remaining therein.
U.S. Pat. No. 3,378,167 discloses apparatus for a self-service auto wash unit in which compressed air is blown through a water hose to remove any remaining water to avoid any possible freezing within the pipe.
U.S. Pat. No. 3,845,779 discloses and evacuating system for a garden hose in which compressed air can be introduced into the hose in order to discharge residual water therefrom.
In U.S. Pat. No. 3,378,167 a relatively complex system is employed in which an electrical timing system is utilized to selectively connect an air compresser to the hose to be evacuated.
In U.S. Pat. No. 3,845,779 an attachment is employed which fits between a water faucet and a water hose and selectively allows compressed air to be discharged through the hose to evacuate the same. The construction of the fitting, however, does not lend itself to use with metal water pipe systems.